Stair tread



FIG. 1 is an upper perspective view of a stair tread showing my newdesign.

FIG. 2 is front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a side view thereof; and,

FIG. 6 is an opposite side view thereof.

The bottom of the stair tread, which is not illustrated in the drawings,forms no part of the claimed design.

CLAIM The ornamental design for a stair tread, as shown and described.